Sealing System For Fill Pipe Head And Associated Pipe

ABSTRACT

Sealing system for fuel tank fill head comprising:
         a valve ( 3 ) that can be moved between an open position, in which fuel may be introduced into a fill pipe, and a closed position in which the fill pipe is closed, the valve ( 3 ) passing from one position to the other under the effect of a pressure exerted by a filling nozzle head; and   a locking system comprising at least two rotatable fingers ( 4 ) and an actuation system capable of controlling the moveable fingers ( 4 ),
 
the system additionally comprising a rotatable ring ( 1 ) equipped with pins ( 5 ) that are capable of cooperating with the moveable fingers ( 4 ) and the valve ( 3 ) that comprises housings ( 6 ) that are capable of cooperating with the moveable fingers ( 4 ) when the sealing system is in a locking position.
       

     The invention also relates to a fill pipe equipped with such a sealing system.

The present invention relates to a sealing system for a pipe for fillinga fuel tank having a locking system capable of being activated by theintroduction of a fuel nozzle.

The fill pipes present in fuel tanks, in particular the tanks aboardmotor vehicles, are sealed during normal use of the tank, when not beingfilled. The sealing is generally achieved either by means of a cap or bymeans of a sealing system integrated into the fill pipe, often called a“capless” system.

More elaborate sealing systems are generally equipped with a lockingsystem capable of keeping the valve in a closed position so that, whennot being filled, the fill pipe is sealed against fuel losses and thataccess to the inside of the pipe is only possible when the lockingsystem has been forced into an unlocked position.

Thus, known from U.S. Pat. No. 5,145,081 is a sealing system equippedwith a locking system comprising a bayonet-type ring. The systemdescribed additionally comprises a flapper valve that pivots under theeffect of introducing a filling nozzle head. The flapper is equippedwith lugs which, when the system is locked, cooperate with the bayonetso as to lock the flapper in a closed position. The bayonet is alsoequipped with notches so that, in the unlocked position, the lugs nolonger cooperate with the bayonet and are released from the bayonet viathe notches. In such a system, the flapper is generally equipped with agasket, for example of the O-ring type, positioned on the side of theflapper oriented towards the outside of the pipe and intended to come tobear against a seat of the head body to which the pivoting flapper isattached. Considering that the gasket is sized so as not to cause therelease of the lugs relative to the notches of the bayonet, the size ofthe pipe head is increased. The size of the system described in U.S.Pat. No. '081 is additionally increased by the space occupied by thesystem (comprising the components 65 to 67 from FIGS. 2 and 3 of U.S.Pat. No. '081) for actuating the bayonet. This is because the actuationsystem is positioned at the side of the pipe head and is not integratedinto it.

Such a system has the disadvantage of a large-sized pipe head.

The object of the invention is to overcome the disadvantage describedabove and to provide a sealing system equipped with a locking system sothat the size of the pipe head is reduced.

For this purpose, the invention relates to a sealing system for a fueltank fill head comprising:

-   -   a valve that can be moved between an open position, in which        fuel may be introduced into a fill pipe, and a closed position        in which the fill pipe is closed, the valve passing from one        position to the other under the effect of a pressure exerted by        a filling nozzle head;    -   a locking system comprising at least two rotatable fingers and        an actuation system capable of controlling the moveable fingers,        the system additionally comprising a rotatable ring equipped        with pins that are capable of cooperating with the moveable        fingers and the valve that comprises housings that are capable        of cooperating with the moveable fingers when the sealing system        is in a locking position.

The valve makes it possible to close the fill pipe of the fuel tank. Ina “capless” type system (with automatic opening of the valve), the valvetakes the place of the closure cap conventionally screwed onto the pipehead by the user. In such a system, the valve is generally firmlyattached to a pipe head body so as to be able to be moved from a closedposition to an open position under the effect of a pressure exerted by afilling nozzle head.

The expression “fuel tank” is understood to mean any type of tank ableto store a liquid and/or gaseous fuel under varied pressure andtemperature conditions. Those more particularly targeted are tanks ofthe kind found in motor vehicles. The expression “motor vehicle” isintended to include motor cars, motorcycles and trucks.

The fill pipe is a pipe which communicates with the inside of the tankand allows fuel to be introduced into it.

The tank and the pipe may be made of metal or of plastic.

The sealing system according to the invention is very suitable for atank and fill pipe assembly in which at least one of the two componentsof the assembly is made of plastic. It is particularly suitable for anassembly in which the fill pipe is made of plastic. As a preference,this sealing system itself comprises at least one part made of plastic.As a strong preference, it is mainly made of plastic.

The term “plastic” is understood to mean any material comprising atleast one synthetic polymer resin.

Any type of plastic may be suitable. Particularly suitable plasticsbelong to the category of thermoplastics.

The term “thermoplastic” is understood to mean any thermoplasticpolymer, including thermoplastic elastomers, and also blends thereof.The term “polymer” is understood to mean both homopolymers andcopolymers (especially binary or ternary copolymers). Examples of suchcopolymers are, non-limitingly: random copolymers, linear blockcopolymers, other block copolymers and graft copolymers.

Any type of thermoplastic polymer or copolymer, the melting point ofwhich is below the decomposition temperature, is suitable. Syntheticthermoplastics having a melting range spread over at least 10 degreesCelsius are particularly suitable. Examples of such materials includethose that exhibit polydispersion in their molecular weight.

In particular, it is possible to use polyolefins, polyvinyl halides,thermoplastic polyesters, polyketones, polyamides and copolymersthereof. A blend of polymers or copolymers may also be used, similarlyit is also possible to use a blend of polymeric materials withinorganic, organic and/or natural fillers such as, for example butnon-limitingly: carbon, salts and other inorganic derivatives, naturalor polymeric fibres. In particular, fibre-filled (for exampleglass-fibre-filled) polyamides are particularly suitable.Advantageously, at least some of these polymeric materials contain aconductive filler (carbon black, for example) in order to avoid problemsassociated with static electricity. It is also possible to usemultilayer structures composed of stacked and joined layers comprisingat least one of the polymers or copolymers described above.

The sealing system that the invention aims to lock has the role ofacting as a cap which seals the upper part of the fill pipe when thetank is not being filled, with a view to avoiding any release and lossof liquid fuel and vapour into the atmosphere when the tank containsfuel.

This sealing system according to the invention is built into the fillpipe head, that is to say is incorporated into a set of parts which aremounted on the upper end of the fill pipe and the purpose of which is toguide a fuel-dispensing nozzle and make filling easier. To do this, thepipe head comprises an opening that communicates with (is in theextension of) the fill pipe and that the valve of the system accordingto the invention makes it possible to seal, in a leaktight manner, whenin the closed (locked) position. This fill opening generally emergesinto a filling bowl (or concave indentation in the body of the vehicleand which is generally sealed by a flap known as a fuel filler flap).

The sealing system according to the invention preferably allows the pipeto be opened automatically via the action of the filling nozzle(obviously when the locking system is in the unlocked position). Theexpression “opened automatically” is to be understood as meaning openedby the action of the pump nozzle alone, to the exclusion of any othermechanical influence. The pump nozzle is the nozzle fitted to theflexible fuel pump hoses in service stations.

The sealing system comprises a valve, that is to say a device thatprevents the passage of gases and liquids through the aforementionedopening in the pipe head. This valve may be in various forms. One formthat is particularly suitable is the form of a moving plate which blocksthe passage when in the closed position. As a preference, this platepivots about an axis. It is advantageously made of plastic but ispreferably equipped with a metal cover, particularly for aestheticreasons and for resistance to abrasion (wear following numerousinsertions of filling nozzles). A gasket is generally joined to thevalve so as to enable leaktight closure of the head of the fuel tankfill pipe, thus avoiding contamination of the atmosphere by liquid orgaseous fuel. The gasket is generally positioned on a side of the valveoriented towards the outside of the pipe and is capable of cooperatingwith a seat positioned on the body of the pipe head. It may, forexample, consist of an O-ring or flat gasket.

According to the invention, the valve is equipped with a locking systemwhich comprises at least two rotatable fingers and an actuation systemcapable of controlling the movement of the moveable fingers.

The moveable fingers are generally able to be rotated about an axissubstantially parallel to the longitudinal axis of the fill head. Forthis purpose, each finger is preferably associated with a vertical rodfirmly attached to the pipe head and onto which rod the finger isinserted (via an ad hoc opening made in the finger). Each of these rodsrespectively acts as an axis of rotation for the finger with which it isassociated.

According to the invention, the valve also comprises at least twohousings capable of cooperating with the moveable fingers when thesealing system is in a locking position, so that access to the pipe isnot possible.

Preferably, the locking system comprises at least three moveable fingersthat are positioned symmetrically relative to the longitudinal axis ofthe fill head and therefore also at least three housings capable ofcooperating with the moveable fingers. In the (most common) case wherethe valve and ring respectively have a disc and ring shape, that amountsto distributing the housings and the fingers at 120° to one anotherrespectively in the lateral surface of the valve and over the lowersurface of the ring.

Also preferably, the housings are produced in the valve and have anopening oriented substantially orthogonal relative to the longitudinalaxis of the fill head. Most particularly preferably, these housings haveat least one of their surfaces (that against which the moveable fingerspress) sloped so that when the system is locked the moveable ring andthe valve compress the gasket. In this variant, it is advantageous forthe moveable fingers to be substantially thinner (narrower) than theopenings in the valve and to be equipped with an excrescence ofappropriate shape and size so that the fingers slide over theaforementioned sloped surface with the aid of said relief alone, whichreduces the (un)locking force.

The actuation system comprises a rotatable ring (preferably that canrotate about an axis corresponding to that of the pipe head, i.e. thatpasses through the centre of the fill opening and that is substantiallyparallel to the axis of the upper part of the fill pipe) and equippedwith pins that are capable of cooperating with the moveable fingers.

In one particular embodiment, each moveable finger has a guide—intendedto receive a pin of the moveable ring so that when this ring is rotated,each pin exerts a force on the guide which has the effect of moving amoveable finger. This guide preferably has a suitable shape and size inorder to ensure that the fingers effectively rotate about their axiswhen the ring turns. Preferably, this shape is substantially oblong.

The rotation of the ring may be actuated by any known means and inparticular by the opening/closure of a fuel filler flap via a rodlinkage system or by a train of gears and of pinions as described inApplication FR 06.04579 in the name of the Applicant. It may also becontrolled by any remote control system.

More preferably, the ring has a substantially circular shape.

The invention also aims to cover a fill pipe for a fuel tank equippedwith a sealing system such as described above, and also a fuel tankequipped with such a pipe.

DESCRIPTION WITH THE AID OF FIGS. 1 TO 4

Other particularities and features of the invention will appear from thedescription of an advantageous embodiment given below, by way ofillustration, with reference to the appended drawings which show:

FIG. 1: overview of a sealing system from the prior art.

FIG. 2 exploded view of the system according to the invention.

FIGS. 3 & 4: overviews of the embodiment from FIG. 2.

A “capless” type sealing system for a fill pipe head of a fuel tank isgenerally represented in FIG. 1. Such a system comprises a valve (3), alocking system for the valve comprising a bayonet-type ring (or morespecifically: a closure system comprising a ring (1) equipped withnotches intended to cooperate with lugs (8) on the valve according to abayonet mechanism). In FIG. 1, the ring (1) is equipped with notches (7)capable of cooperating with lugs (8) positioned on the side orientedtowards the outside of the valve (3). In the unlocked position of thesealing system, the lugs (8) do not cooperate with the ring (1) so that,under the effect of introducing a filling nozzle, the valve (3) may beretracted to an open position capable of giving access to the fill pipe.In the locked position, the lugs (8) cooperate with the ring (1) so thatit is not possible to access the fill pipe. The opening/closingoperating mode is known per se and is not described in detail in thepresent patent application. As will be seen by comparison with thefollowing figures, such a system (although effective) has thedisadvantage of being bulky, considering the size of the lugs (8) whichare fixed. Moreover, the gasket (not represented) must be of a largesize since it must go round the openings in the head which are necessaryfor the passage of the lugs (8) when the valve (3) pivots to allow thetank to be filled.

Represented in FIG. 2 is an embodiment of a system according to theinvention with a valve (3) equipped with housings (6), a ring (1)equipped with pins (5) and moveable fingers (4). The moveable fingers(4) are positioned on a body (2) (which is in fact the body of the pipehead) and have guides (9) which cooperate with the pins (5) so that whenthe ring (1) is rotated, the moveable fingers (4) are also made torotate. This rotation is carried out about rods (2′) which are firmlyattached to the body (2) and over which the fingers (4) are slipped bypassing through openings (4′).

FIGS. 3 and 4 illustrate the system from FIG. 2 where the sealing systemis in a locked position. In this position, the moveable fingers (4),which are firmly attached to the body (2) of the pipe head, cooperatewith the housings (6) of the valve (3) so that this valve is in theclosed position and so that a gasket (not represented) is compressedover a seat of the body (2). As can be seen in FIG. 4, the upper wall ofthese housings (6) is sloped so that the fingers (4) slide over thisslope with their balls (4″) and by doing so (de)compress the gasket.

The moveable fingers (4) are moved under the effect of the rotation ofthe moveable ring (1). Specifically, the ring (1) is equipped with 3pins (5) which each cooperate with a guide (9) made in a moveable finger(4) so that, when the ring (1) is moved, each pin (5) exerts a force ona guide (9) and has the effect of rotating a moveable finger (4).

1. A sealing system for fuel tank fill head comprising a valve (3) thatcan be moved between an open position, in which fuel may be introducedinto a fill pipe, and a closed position in which the fill pipe isclosed, the valve (3) passing from one position to the other under theeffect of a pressure exerted by a filling nozzle head; and a lockingsystem comprising at least two rotatable fingers (4) and an actuationsystem capable of controlling the moveable fingers (4), the systemadditionally comprising a rotatable ring (1) equipped with pins (5) thatare capable of cooperating with the moveable fingers (4) and the valve(3) that comprises housings (6) that are capable of cooperating with themoveable fingers (4) when the sealing system is in a locking position.2. The sealing system according to the preceding claim, wherein eachfinger (4) is associated with a vertical rod (2′) firmly attached to apipe head body (2) and onto which rod the finger (4) is inserted via anopening (4′) made in the finger (4).
 3. The sealing system according toclaim 1, wherein the locking system comprises at least three moveablefingers (4) that are positioned symmetrically relative to thelongitudinal axis of the fill head.
 4. The sealing system according toclaim 1, wherein the housings (6) are produced in the valve (3) and havean opening oriented substantially orthogonal relative to thelongitudinal axis of the fill head.
 5. The sealing system according tothe preceding claim, in which the housings (6) have at least one slopingsurface against which the moveable fingers (4) press, so that when thesystem is locked the moveable ring (1) and the valve (3) compress thegasket.
 6. The sealing system according to the preceding claim, in whichthe moveable fingers (4) are substantially thinner (narrower) than thehousings (6) and are equipped with an excrescence (4″) of appropriateshape and size so that the fingers (4) slide over the sloped surface ofthe housings (6) with the aid of said relief.
 7. The sealing systemaccording to claim 1, wherein each moveable finger (4) has a guide (9)intended to receive a pin (5) of the moveable ring (1) so that when thisring is rotated, each pin (5) exerts a force on the guide which has theeffect of moving the moveable finger (4).
 8. The sealing systemaccording to the preceding claim, in which the guide has a substantiallyoblong shape.
 9. A fill pipe for a fuel tank equipped with a sealingsystem according to claim
 1. 10. The fuel tank equipped with a fill pipeaccording to the preceding claim.